A vehicle system may include one or more powered vehicles that may be mechanically linked (directly or indirectly) to non-powered vehicles. The powered and non-powered vehicles of the vehicle system may travel as a group along a designated route. In cases where the vehicle system includes multiple powered vehicles, the vehicle system may coordinate operations of the powered vehicles to move the vehicle system. For example, a rail vehicle system may include a powered unit consist that has one or more powered units mechanically coupled to one or more non-powered rail cars. Vehicles in a consist may include a lead powered unit and one or more remote powered units and/or trail powered units. (Remote powered units are those that are spaced apart from the lead powered unit by one or more non-powered vehicles. Trail powered units are those that are in the same powered unit consist as the lead powered unit, and thereby not spaced apart from the lead powered unit by one or more non-powered rail vehicles, but that are subordinate to control by the lead powered unit). The lead vehicle may control operation of one or more remote vehicles.
In certain vehicle systems, a lead vehicle communicates with remote powered vehicles via a multiple unit (MU) line. Conventional MU communications do not identify a particular remote vehicle for which a command is intended. Instead, a similar command is sent to all remote vehicles. Ethernet over MU signals may be overlaid on one or more channels of a MU line, and may include identification information of a sender or intended audience. However, such identification information may only be useful when a receiving vehicle has previous knowledge of the identity or location of a sender.
In certain vehicle systems, fuel cars (also known as fuel tenders) may be employed to carry fuel and to supply fuel to one or more powered vehicles. For example, liquid natural gas (LNG) or compressed natural gas (CNG) may be employed as a fuel source for one or more powered vehicles. However, LNG and CNG may not be readily available along a route traversed during a mission. Thus, fuel cars may be added to a consist to provide additional fuel carrying capability. Further, fuel cars may be replaced and/or added at various points during performance of a mission to provide additional fuel. As powered vehicles consume fuel during a mission, those vehicles that require additional fuel may request fuel from a fuel car. A fuel car may be operably connected with plural vehicles, for example, via separate, dedicated fuel supply lines. For proper response to fuel requests, the fuel car must be able to determine which fuel supply line provides fuel to a particular vehicle requesting fuel. Because communications utilizing MU or Ethernet over MU communications may be configured so that all vehicles have access to messages, it may be difficult to determine which vehicle is requesting fuel. It may be desirable to have a system or method that differs from those that are currently available.